Summary The CL-600-2B16, N8MC, serial number 5329, departed Iqaluit, Northwest Territories, en route to Seattle, Washington, and was initially cleared direct to the geographic point of latitude 63 degrees north (N) and longitude 080 degrees west (W) at flight level (FL) 240, and then subsequently to FL 350. British Airways Flight 279 (BAW279), a Boeing 747-400, G-BNLK, was en route from London-Heathrow, United Kingdom, to Los Angeles, United States, via Iqaluit at FL 350. To ensure the required spacing between the two aircraft, N8MC was to be re-routed via 64N 070W, then to 63N 080W, with a restriction to remain at FL 330 or below until reaching 64N 070W. By the time this change in routing and the restriction was actually given to the pilots of N8MC, they had already flown past 070W and were intercepting the amended outbound track. In order to determine the impact of the routing change on other traffic, the data controller working at the Montreal Area Control Centre (ACC), Nuvilik sector, used the radar data processing system (RDPS) to display the track for N8MC on a nearby radar display. However, in entering the new route, the data controller inadvertently entered the wrong coordinates for the second point along the route and was thereby convinced that N8MC's position was much farther north in relation to BAW279 than it was in reality. This error was not detected by the controller. As a consequence, the altitude restriction to remain below FL 330 was cancelled. Lateral spacing between BAW279 and N8MC was reduced to approximately 9 nautical miles (nm) laterally and 1,500 feet vertically, where 20 nm or 2,000 feet was required. Ce rapport est galement disponible en franais. Other Factual Information The Montreal ACC is made up of four specialties, East, North, South and Terminal, each of which is further divided into a number of sectors. The North specialty is a high-level specialty which controls air traffic FL 290 and above for most of the province of Quebec as well as the north-eastern approaches into Canadian airspace from the oceanic control areas. The East specialty is a low-level specialty responsible for controlling most of the province of Quebec north of 47N latitude, with the exception of Qubec City areas. Individual sectors within a specialty may be controlled individually or combined, depending on operational requirements on a particular day. The East specialty of Montreal ACC is composed of five sectors. On the morning of the occurrence, these five sectors had been combined into two, one of which was comprised of James Bay, Hydro, and Nuvilik sectors. This was a normal and accepted procedure for a Sunday morning. Iqaluit Airport lies within the Nuvilik sector. The combined Nuvilik/James Bay/Hydro sector extends up to and including FL 280. These three sectors have partial radar coverage. Non-radar control procedures are utilized where radar coverage is not available. The airspace in which this occurrence took place was beyond radar coverage. The Brevoort sector is one of the sectors within the North specialty of Montreal ACC, and controls the airspace overlying the northern part of the Nuvilik sector from FL 290 and above, as well as the oceanic approaches to northern Canada. Radar coverage in the Brevoort sector is available from the sector's eastern boundary to a few miles west of Iqaluit. The North specialty is equipped with the Northern Airspace Display System (NADS), which provides a visual display of the estimated and/or confirmed positions of aircraft flying within the sector and provides conflict prediction. Staffing in the East and North specialties of the Montreal ACC at the time of the occurrence was in accordance with unit policies and was reported to be compatible with the workload. The traffic volume and complexity were assessed as moderate. The combined Nuvilik/James Bay/Hydro position was staffed with a data controller and a radio controller who was monitoring a trainee in the radio position. It is the radio position that was in direct contact with the aircraft and was responsible for initiating control actions to separate aircraft. The data controller maintains the data board and coordinates flight information with other sectors and units. The supervisor for the East specialty was working another control position at the time of the occurrence. The supervisor for the North specialty was standing back and assisting with coordination of flight information as required within his own specialty. At the time the North specialty controller issued the revised route and altitude restriction to N8MC, the East specialty Nuvilik/James Bay/Hydro sector radio controller, a trainee monitored by an on-the-job instructor (OJI), was busy with other traffic in the southern part of the combined sector and was using the Chibougamau radar to provide radar control services there. It is the role of the OJI to provide the trainee with on-the-job experience while at the same time ensuring compliance with all applicable rules and regulations pertaining to the provision of air traffic control services. The OJI must be able to monitor closely all air traffic control (ATC) communications and take over the position from the trainee without requiring a briefing from the trainee. The OJI is provided training in instructional, interpersonal, and debriefing techniques in accordance with NAV CANADA-approved training courses. A controller may volunteer to receive initial training to become an OJI. The Nuvilik radio controller was expecting Air Baffin Flight 200 (BFF200), a Beech 200 aircraft flying from Puvirnituq, Quebec, at FL 250 and estimating Iqaluit at 1415.(1) At 1337, the Nuvilik radio controller issued a clearance to BFF200, through Kuujjuaq Flight Service Station (FSS), to fly the 275 radial of the Frobay very high frequency omni-directional range (VOR) inbound to Iqaluit and to maintain FL 250. On initial contact with BFF200, 92 nm south-west of Iqaluit at FL 250, the Nuvilik radio controller cleared BFF200 to maintain 16,000 feet above sea level (asl) (see Appendix A - Sequence of Events). At the same time, the Brevoort sector in the North specialty was controlling BAW279, which reported to the Brevoort sector controller that it had passed the Frobay VOR, located 2.4 nm south-east of the Iqaluit Airport at 1354, at FL 350, and was estimating BODRA intersection located at 6217'N 080W at 1433. N8MC departed runway 18 at Iqaluit Airport at 1341, with a clearance from Iqaluit direct to a geographic position of 63N 080W (see Appendix B - Relative Aircraft Tracks), outbound on the 308 radial of the Frobay VOR, and with a clearance to climb to FL 240. On departure, N8MC was issued a restriction to cross 20 nm from the Frobay VOR, at 15,000 feet asl or below, to ensure the required separation between N8MC and BFF200. Five minutes later, at 1346, N8MC reported crossing 21 nm, upon which the Nuvilik radio controller issued a clearance for N8MC to climb to FL 280 and to report passing FL 240. The North specialty Ungava NADSposition accepted the departure time for N8MC from the Nuvilik data controller and subsequently confirmed that FL 350, along with an amended route and an altitude restriction, was acceptable. At 1349, eight minutes after N8MC departed Iqaluit, one minute after BAW279 had estimated passing overhead the Frobay VOR, the Nuvilik radio controller issued a revised altitude and altitude restriction, received from the Brevoort sector, to N8MC, to climb to FL 350 and to cross 64N 070W at FL 330 or below. This position was not on the route initially given to N8MC. Moments later, the radio controller issued a revised route to N8MC to proceed from the aircraft's present position direct 64N 070W, then 63N 080W, then on the flight-planned route. The controller also reiterated the restriction to remain at FL 330 or below. One and a half minutes later, the pilot of N8MC reported that the aircraft had already passed 64N 070W and was turning right to intercept the route to 63N 080W. The pilot also asked for confirmation that it was the correct action, to which the radio controller replied in the affirmative and, at 1353, N8MC requested confirmation that a climb to FL 350 was now authorized. The Nuvilik controller then realized the aircraft had passed 070W and immediately approved the climb to FL 350. Thirty seconds later, the Nuvilik radio controller asked N8MC if the aircraft was established on the track between 64N 070W and 63N 080W, to which the pilot responded that he was 12 nm to the east of the track, heading toward it. The Nuvilik radio controller then stated to the pilot that the aircraft must be established on the specified track and to maintain FL 330 or below until established on the track. One minute later, at 1356, the pilot indicated, as a result of a request from the controller, that the aircraft was now 5 nm from the track and was complying with the restriction to remain at FL 330 or below until established on the track. Almost immediately, the data controller advised the radio controller that the high-level sector had cancelled all restrictions for N8MC. The Nuvilik radio controller informed N8MC of the cancellation and requested a report when level at FL 350 and an estimate for 63N 080W. Three minutes later (at 1358:48), the Nuvilik radio controller advised the pilot of N8MC that the next sector was unable to accept the aircraft at FL 350, and that the flight was to descend to FL 310. The pilot stated that the aircraft was climbing through FL 335 and that he was descending back to FL 310. At 1402, N8MC reported levelling at FL 310, and shortly thereafter, indicated the aircraft was 127 nm from the Frobay VOR. The two aircraft (N8MC and BAW279) came within 9 nm and 1,500 feet of each other while procedures require a lateral separation of 20 nm or vertical separation of 2,000 feet. At no time did the Nuvilik radio controllers (trainee nor OJI) ascertain the exact position of N8MC, either by requesting a position from the Frobay VOR, or an exact latitude/longitude. There was some discussion between the trainee and the OJI as to the position of this flight relative to the track and the applicability of the altitude restriction, but the OJI did not direct the trainee to specifically confirm the exact position of the flight. Because the trainee and OJI were busy with other traffic in the southern sector under radar control, they were unaware of the efforts of the Nuvilik data controller trying to resolve the conflict between N8MC and BAW279 with the North specialty controllers and supervisor, and thereby allow N8MC to continue the climb without requiring the flight to level off at an intermediate altitude. The Nuvilik data controller was responsible for coordinating clearances (and other flight information for N8MC) with other sectors in the Montreal ACC. After the Nuvilik data controller received the departure time for N8MC from Iqaluit FSS, he passed the information to the Ungava NADS position. Shortly thereafter, the Ungava NADS controller issued a restriction for N8MC to the Nuvilik data controller. N8MC was to be re-routed via 64N 070W, and restricted in altitude to cross that position at FL 330 or below, to provide the required separation with BAW279. This information was placed on the flight progress strip for N8MC by the NADS controller, handed to the Nuvilik data controller who then placed the flight progress strip in the appropriate section of the data board for the radio controller. The data controller was unable to verbally brief the radio controller on the restriction because the sector radio controller was busy with other control duties, but he physically pointed out the strip to the OJI. The trainee radio controller, however, did not pass this restriction until N8MC had climbed above FL 250. He reasoned that, once N8MC was above this altitude, it would be clear of the conflicting inbound traffic, and could then be safely re-routed in any direction as it continued the climb. Neither the trainee nor the OJI perceived that there was a requirement to pass on the restriction quickly because of the proximity of the new coordinate to Iqaluit, nor the rapidity at which N8MC was climbing; the CL600 Challenger executive jet is known by controllers to be capable of a rapid climb to altitude. Aircraft departing Iqaluit and climbing into the high-level airspace are initially cleared to maintain an altitude of FL 280 or below. Once the flight departs, coordination is initiated with the high-level sectors for route and higher-altitude approval. It is the controller at the NADS position who activates the information on the flight and determines if there are any conflicts with other traffic. The route and altitude approval and any restrictions are then passed to the low-level sector for relay to the aircraft. Once the flight is clear of any conflict in the low-level sector's airspace, control is then passed to the high-level sector. There are normally few delays encountered by departing traffic from Iqaluit with this method of operation, as the traffic levels are normally low. Controllers working in the low-level Nuvilik sector are generally not as cognizant of where latitude/longitude coordinates are situated in relation to airports, geographic reference points, navigational aids, or the intersections they more normally use in their day-to-day controlling activities. There was no plotting board at the Nuvilik/James Bay sector position; normally there would be one at that position. It is the controller's responsibility to ensure that all required equipment is available. The plotting board includes a chart covering the controller's area of responsibility and a specialized ruler to determine aircraft tracks between different points and the airspace to be protected for a particular aircraft. It could not be determined, during the investigation, why there was no plotting board at the Nuvilik sector. Many controllers consider the plotting board a less accurate method of depicting aircraft tracks when compared with using the range bearing line (RBL) function of the RDPS. This function allows controllers to enter two coordinates and display the resulting track between the two points on the radar display. The trainee radio controller was, however, busy with traffic in the southern sector, so the radar display could not be de-centred to the area around Iqaluit without losing the radar information for the southern sector. In an effort to assist, the data controller walked over to another, unused console on the other side of the operations room and entered into the RDPS what he thought were the correct coordinates for the new route N8MC was to fly. There was a perceived urgency by the Nuvilik data controller to complete this action as N8MC was quickly approaching Brevoort sector controlled airspace and would have to be handed over to that sector soon. The Nuvilik data controller intended to use the RBL to compare the track originally requested by the pilot with the revised track. He correctly typed in the coordinates for the originally cleared track from Iqaluit to 64N 080W. For the revised track, however, the data controller incorrectly typed in the second position as 65N 080W instead of 63N 080W. This resulted in a displayed track which was considerably farther north than the originally requested track, and also farther north than the amended track issued in conjunction with the altitude restriction. The Nuvilik data controller did not detect the error and therefore surmised that N8MC was to the north of the revised track, and so informed the North specialty supervisor. The North specialty supervisor then informed the Nuvilik data controller that the FL 330 altitude restriction was cancelled. This information was then passed by the Nuvilik data controller to the Nuvilik radio controller. The Nuvilik radio controller kept N8MC on his frequency in order to ensure communication and separation with BFF200 inbound to Iqaluit. The Nuvilik sector serves as a relay for the Brevoort sector, as this sector does not have any communications capability with aircraft departing Iqaluit. If the Brevoort sector has any restrictions or instructions for aircraft climbing to high-level airspace, that information will be relayed via the Nuvilik sector. While serving as a relay, it is not always considered necessary that the Nuvilik controllers have all the traffic information in the high-level airspace. However, Nuvilik controllers are responsible for providing separation for flights within their own area of responsibility up to FL 280. The Nuvilik radio controller, therefore, had to confirm where the revised route would take N8MC and determine how this restriction would affect separation with BFF200. The North specialty controller, on the other hand, was not made aware that the revised routing might affect separation with another aircraft in the Nuvilik sector and thereby result in a delay in passing the restriction to N8MC. In a restructuring between the East and North specialties, which took place a few years before this occurrence, a number of the more-experienced controllers were moved to the North specialty. As a result, the East was left with reduced controller experience levels. It was generally accepted that the North specialty was a more difficult specialty in which to qualify. It was also perceived by some controllers that it was easier to qualify in the East. This led to somewhat strained communication between the two specialties, which affected the ease with which information was exchanged. As a result, a lack of cooperation and an underlying climate of dissonance had been allowed to fester between the two specialties and, at times, hindered the free flow of communications between the North and the East specialty controllers during this particular shift. For example, the Nuvilik data controller did not ask the North supervisor for more information relating to the revised route for N8MC (which the data controller knew was available on the NADS display) in the North specialty, but chose instead to add to his own workload by plotting the tracks himself at another console. Communication problems were not evident in other specialties in the ACC. Shortly before this occurrence, a new manager responsible for the East specialty was appointed, and it was reported that communication between the two specialties had improved.